Coral ID is the encyclopedia for coral species.

Acropora is the most species-rich genus among the small polyp stony corals. The exact determination of different species is often difficult due to the interconnected evolution of this genus, and causes difficulties even for experts.

Typical for Acropora is that at the end of branches there is a single polyp. There are both flat table-shaped and branched growing species, which are then called table corals or staghorn corals.

Acropora became popular from the mid 90's after the so-called Berlin system (with skimmer and live rock) made keeping them possible. They have high demands on water quality and require intense lighting, which makes them demanding to keep. However, under the right conditions they grow quite fast and show their full splendor.

Acropora SPS are easy to propagate by frags, which can also be easily snipped off with pliers and glued on with super glue. Therefore they are widely spread in the marine aquarium hobby and are often traded among aquarists, which also brings many different fantasy names for the different color morphs. Under blue light with orange filter, amazing colors often appear, for example Acropora tenuis Walt Disney or Homewrecker, Acropora microclados Strawberry Shortcake or Acropora echinata Icefire.

Alveopora are called flower pot corals and are related to Goniopora and Bernadpora. The difference between corals of the genus Alveopora and Goniopora is the number of tentacles on the polyps: Alveopora have 12 tentacles, whereas Goniopora have 24 tentacles.

The length and size of the polyps of the corals can vary between the different species. Usually no exact species classification is possible anyway, because the differences are too small. Green and gray color forms are common, sometimes in different pastel shades.

Keeping Alveopora flower pot corals can be demanding. Flower Pot corals are mostly found in lagoons, often with high turbidity and changing currents. It is therefore best to give them a shaded spot with varied but gentle flow. They thrive best with slightly elevated nutrient levels, and they like to be fed additional fine planctonic dry or live foods. If they do not open, try placing them in a different location.

Chalice is a collective term for a number of "chalice-shaped" large polyp stony corals, which are very difficult to distinguish from each other on the living animal and on sight. For example, Echinophyllia, Echinopora, Echinomorpha, Mycedium, Oxypora, and Acanthastrea echinata are sometimes referred to as Chalice. These stony corals are extremely popular as there are fantastic color morphs, from forms referred to as Watermelon and Rainbow to Afterburner, Convict, Mummy Eye, Mindbender, Hollywood Stunner and many more.

Although the name suggests a cup-shaped growth, many Chalices are not free-standing, but encrust creeping over rock. Since a wide variety of species are traded as Chalices, growth rates range from very slow to moderately fast. Generally, most Chalices like a shady location around 40 PAR, with very blue-heavy light color for good color development. If the light intensity is too high, they easily get burned and bleach. Important for a good development are also higher nutrient values: especially phophate should be present and detectable, optimally around 0.1 mg/l, with nitrates around 10-20 mg/l.

When placing chalice corals, care should be taken that many among them can sting powerfully and form surprisingly long fighting tentacles. Therefore, it is best to place them at a generous distance from other corals.

Condylactis is a genus of anemones with representatives found all over the world - for example the golden anemone Condylactis aurantiaca in the Mediterranean Sea or - much more interesting for us saltwater aquarists and the only representative in our aquariums - the giant Caribbean sea anemone, giant golden anemone ot Haitian anemone Condylactis gigantea. Typical is a quite compact body with long, thin tentacles.

Cyphastrea is a coral genus belonging to the large polyp stony corals (LPS = Large Polyp Scleractinia). The coral colonies of most species grow flatly encrusting over the substrate, or in lumpy boulders. Only Cyphastrea decadia grows branched. A clear separation of the species is really only possible microscopically from the skeleton, but many animals in the trade should be Cyphastrea serailia or Cyphastrea ocellina according to the distribution in the Indopacific. Popular color morphs are "Forest Fire" or "Meteor Shower", for example.

Cyphastrea can be distinguished from Montipora and other flat growing stony corals by the fact that the polyps are crater- to nodule-shaped and the space between them is normally smooth.
The location of Cyphastrea stony corals in the marine saltwater aquarium should be shady, in our tanks the mother colonies become most beautiful at about 40 PAR. About the care: Slightly increased nutrient values are good for growth. Cyphastrea are well suited to occupy vertical surfaces on pillars similar places, as they grow well on these even with little light.

Discosoma is a coral genus of colonial anemones from the order Corallimorpharia - sometimes shortened to "morph". Alternatively, due to their shape, they are also called "mushrooms" or abbreviated as "shrooms".
There are different species of Discosoma, but the differentiation is normally not easy, except for special representatives like Discosoma carlgreni or Discosoma neglecta with distinct shapes. The distinguishing feature is single polyps with simple, round shape without tentacles on the edge. The difference between Discosoma and Rhodactis corals is that Discosoma just do not have tentacles on the edge. Nevertheless, on their body they can have different kinds of outgrowths like dots, warts or pseudotentacles. Occasionally representatives of the genus are still listed under the no longer taxon Actinodiscus.

Discosoma are very easy to keep in the aquarium among soft corals, and they grow readily - individual animals usually bud off smaller frags over time, so they can spread quickly, especially as a colony. Individually, this means you can expect them to divide about 1 time per year in the aquarium. Fearless keepers also fragment them by cutting them with a sharp knife, but losses should be expected. They often like it shady and nutrient-rich, and you should be careful not to burn them. Especially the special and rare morphs like Jawbreaker, Mystery Tie-Dye, Eclectus, Kryptonite, and others like it very dark at just 20-30 PAR.

Discosoma and other mushrooms can migrate in the marine aquarium and can also detach from the rock due to bad conditions or stress. To (re)attach Discosoma to rocks, it is best to place them on coarse coral rubble in a dish and wait for them to attach on their own. The piece of coral rubble can then be attached to substrate with gel superglue. Conversely, it is often difficult to remove Discosoma from the rocks - the easiest way is to chip them off along with the underlying rock, using a chisel or pliers. To permanently get rid of unwanted Discosoma as a "nuisance", you can cut them off with a knife and coat the remains with a calcium hydroxide slurry.

Euphyllia is a genus of large polyp stony corals, also called LPS corals. These beautiful corals are characterized by soft tissue with long tentacles that protrude from and can fully retract into a solid calcareous skeleton. Different species differ in the growth form of the skeleton - either flabello-meandroid, growing in a brain-like shape as walls, where the skeletal walls are usually seperated, or branched with single more or less distinct polyps - and the shape of the tentacle tips, where hammer-shaped forms are seen in hammer corals, or branched tentacles with several frogspawn-like tentacle tips, or simple, long tentacles with one tips seen in Torch corals. The following coral species are of particular interest for keeping in a marine aquarium:

• Euphyllia ancora, a flabello-meandroid species of hammer coral,
• Euphyllia divisa, a flabello-meandroid species of frogspawn coral,
• Euphyllia paraancora, a branched species of hammer coral,
• Euphyllia paradivisa, a branched species of frogspawn coral,
• Euphyllia glabrescens, a branched species with long tentacles, which is also called "Torch".
• Euphyllia yayaemensis, a rare branched species with grape-shaped branched tentacles

Other species like Euphyllia cristata, E. paraglabrescens or E. baliensis are not usually found in the trade. The systematics is also in motion with Euphyllia, and after the latest revisions some or all species are also assigned to the new genus Fimbriaphyllia, depending on the author.
Keeping Euphyllia corals in a saltwater aquarium is usually uncomplicated, as with most LPS, because as LPS they have few demands on water quality and like to have more nutrients in the water. In overly clean water Euphyllia corals even often get sick.

Only the KH should be permanently and stably above 8, because they probably react sensitive to pH fluctuations or similar. When handling, one should always take care that the sharp skeleton does not damage the tender tissue, therefore gentle (but turbulent) current is best. The light requirements are weak to medium - about 50-120 PAR.

If Euphyllia frags are injured, they often have problems with bacterial infections or brown jelly - you should then treat them with an antibacterial dip or cut off the damaged area cleanly. When making frags, clean cuts made with a water-cooled band saw, Dremel, pliers or even hammer + chisel should be made, and those normally heal well if conditions are suitabln. So even the flabello-meandroid species are very often only seen as fragments in the trade.

Favia is a genus of reef-building large polyp stony corals, also called LPS. They are typical representatives of the brain coral family, the Faviidae. The exact differentiation of brain corals is complicated, and for many species the systematic classification is now questionable. Therefore, we usually use this name for those representatives in which the outer walls of the corallites are mostly separated.

Favia normally grow flat over the substrate, and with age the colony builds up hemispherically. In the marine aquarium, they are generally uncomplicated stony corals and have few requirements for water quality, light, food, and care. They tolerate slightly increased nutrients, the current should be medium - so that no detritus is deposited on the coral - and the light rather low, because even this LPS can burn in the aquarium with too strong lighting.

Fungia is a genus of large polyp stony corals. Because of their shape they are also called mushroom corals (not to be confused with mushroom soft corals/corallimorphs like Discosoma or Rhodactis). They consist of individual polyps that live freely on sandy areas instead of growing attached to rocky substrate like many other corals. Fungia are easy to keep and well suited for beginners. The corals have few water quality requirements and do well with low to medium light levels and gentle currents in the aquarium.

They can free themselves in the tank by pumping their tissue up to free themselves from sediment and moving or drifting with the current. Thus, these stony corals are at risk of getting stung by other corals and animals that repeatedly bury them in sand and thus harass them - so care should be taken when choosing the right tankmates. Due to recent taxonomic developments, the vast majority of former Fungia species have now been assigned to Cycloseris and other genera, and only the species Fungia fungites remains in the genus and is thus strictly speaking a "true Fungia".

Goniopora is a genus of stony corals from the family Poritidae. They belong to the large-polyp stony corals, although they are actually closely related to the small-polyp stony corals. This relationship is most evident in their skeletal structure. Goniopora, however, have conspicuously long, fleshy polyps that can reach up to 10 cm in length, depending on the species. Because of their shape they are also called margarite corals or in English flowerpot corals. They can fully retract these tentacles into their skeleton when disturbed. In shape they are similar to Alveopora, the difference between Alveopora and Goniopora is that Goniopora have tentacles with 24 tips, while Alveopora have only 12 tentacle tips. Thus, the distinction between Goniopora and Alveopora can be made simply by the number of tentacles. Especially for the species with small polyps the differentiation to Porites and similar species can also be a problem. The species with the smallest polyps, Goniopora stutchburyi, which is commonly called "carpet of love", has meanwhile been classified in its own genus Bernardpora. As a special feature, Goniopora can self-reproduce via offshoots, a process known in science as "fragging," effectively asexually forming their own frags.

Goniopora have a wide distribution range from the Red Sea to the Indian Ocean and into the Pacific Ocean and are distributed as far north as to Hong Kong and southern Japan. They inhabit various reef habitats, but often lagoon areas, some of which are sediment rich. They feed on light via zooxanthellae, but often ingest particulate food as well, so supplemental feeding with plankton or powdered food often promotes vitality. In general Goniopora need higher nutrient levels, otherwise they tend to suffer. As trace elements, manganese and iron are said to be important. For their well-being a varied, changing current is advantageous, but it should never be direct. Since species can originate from different habitats from turbid lagoons to reefs, light requirements can range from very weak to medium. If the Goniopora does not open up and remains closed, one should try several locations with more or less current and more or less light. Also, make sure nutrients are present in the water and try feeding with phytoplankton, oyster eggs or powdered feeds.

Most often Goniopora are green or beige in color, less common are yellow-green animals, occasionally blue-purple and very rarely red color forms. Multicolored Goniopora are especially sought after, like the Golden Inferno Goniopora, which is multicolored red-yellow. Red-blue or green-blue color forms also occur from time to time, and Bernardpora has spectacular orange-based multicolored Rainbow color forms.

Gorgonia is the name-giving genus of the group of horn corals (Gorgonacea) from the family of soft corals (Alcyonacea). They are called gorgonians or sea fans, which is indeed the program here: the shape is usually a fanned lattice. Gorgonians in particular have a horny skeleton made of a flexible material called gorgonine, which is then covered by the tissue, which, as in all soft corals, contains calcareous needles that are an important feature for taxonomic differentiation. Gorgonia are zooxanthellate and can feed on light through their symbiotic algae, but also take up dissolved nutrients and filter food particles from the current. They are mainly distributed in the Caribbean region. For keeping a constant, preferably laminar current is most important, water quality is rather of secondary importance, and light can in principle be tolerated a lot, but this is not a requirement. Several species of Gorgonia exist, but differentiation is difficult and usually of little use, as the requirements are similar. The color is usually purple to gray.

Montipora is a genus of small-polyped stony corals and with currently 85 described species the second most species-rich genus of corals after Acropora. Their natural range extends over the entire Indo-Pacific. Because of their small polyps they are also called pore coral. There are different growth forms, which can also occur mixed depending on species and habitat, from encrusting over the substrate to leaf- to mushroom-shaped staggered pagoda or branch-shaped structures. The exact identification of species is, as with many other corals, not perfectly possible on the live animal, because it requires a microscopic examination of the skeleton. It is also difficult to distinguish them from the very similar Porites species, since they differ only in the skeletal structure of their corallites.

Montipora are generally less demanding than other small-polyp stony corals. They still require tighter control of water values than LPS or soft coral, but among the SPS they are well suited as the first SPS for beginners or as the first SPS when stocking the aquarium. They also generally require less light than Acropora and can tolerate slightly higher nutrient levels. It is also especially important to have a strong current to prevent sediment from settling on their tissue. Popular color forms are for example Montipora "Rainbow", Montipora "Superman", Montipora digitata "Forest Fire" or Montipora samarensis "Bubble Gum".

Platygyra is a genus of stony corals and belongs to the Merulinidae. The growth form is similar to brain corals - colonies are plate-shaped to massive. Most conspicuous are the elongated valleys of polyp walls that encompass several polyps with multiple mouths. The taxonomic situation, as with many corals, is a disaster - differentiation from related species such as Favites or Goniastrea is rarely cleanly possible, and if so then usually only microscopically on dead specimens of the skeleton or by DNA analysis. Revisions are also common. We therefore simply use the name for all brain coral-like LPS plates with the typical polyp valleys.

The requirements are fortunately also similar across species - medium current, medium to weak lighting, nutrients may also be higher - in short: typical for LPS. Most interesting are the different color variations with contrasting colors on the "valleys" and "ridges", often "monochromatic" brown with green/purple, but sometimes both multicolored. In addition, patterned specimens with thin transverse stripes appear especially on the combs.

Plexaura is a genus of soft corals and is counted among the gorgonians. They are distributed mainly in the Caribbean. They differ from other gorgonians mainly by their thick arms, which are arranged like a candelabra and are little branched. The polyps with their 8 arms are clearly recognizable, which confirm the affiliation to the Octocorallia - the eight-rayed flower animals. Some species contain a conspicuously high proportion (2-3% of total mass) of the lipid prostraglandin A in their tissues, which has applications in human medicine as a muscle relaxant, and they were even used as a source of it in the past, before there were ways to synthesize it. It is thought to be a chemical defense against predators.

As a zooxanthellate gorgonian, these horn corals tolerate a lot of light. They require a steady, preferably laminar flow. Little demands are made on the water conditions. For propagation via frags, it is best to peel off the tissue at the point of attachment down to the horn skeleton consisting of gorgonin and use superglue to attach it in a hole on the frag rock.

Pterogorgia is a genus of horn corals and is classified as a gorgonian. They consist of a black horny skeleton of gorgonine and their tissue covering this is interspersed with sclerites - fine calcareous needles, as in other Alcyonidae soft corals. They are distributed mainly in the Caribbean. Their growth is usually feathery branched, the branches are usually all in one plane. Conspicuous are the flattened tentacles, on each side of which sits a row of polyps - therefore they are also called knife gorgonians - currently 4 confirmed species are accepted: Pterogorgia anceps, Pterogorgia guadalupensis, Pterogorgia citrina and Pterogorgia antillarum. Color is mostly beige to purple, with P. citrina ranging from beige to yellow. Lighting should be strong, as

Pterogorgia have zooxanthellae and can photosynthesize. Supplemental feeding is not needed, but is accepted. Water quality should be good, though horn corals are generally hardy. The flow should ideally be strong and laminar, so evenly applied to all points of the animal.

Stylophora is a genus of reef-building stony corals and is classified as Small Polyp Scleractinia (SPS), or small polyp stony corals. They are common and are distributed in the Red Sea, Indian Ocean, and eastern Pacific to Pitcairn. It is more diverse in the Red Sea and western Indian Ocean than in the Indo-Pacific as the only major stony coral genus. Fossil Stylophora are already known since the Mesozoic from the Thethys Sea (until about 200 million years ago). Stylophora grow in a bush-like branching manner, often with finger-thick branches. Their polyps are similar to other members of the Pocilloporidae (Madracis, Pocillopora, Seriatopora) and have nearly transparent tentacles with colored tips. Unlike related species, the branches are usually over 10 mm thick, the thickness often corresponding to the extent to which the corals are exposed to currents and tides. The color is usually brown to greenish, popular are especially the rarer pink specimens from the South Seas, for example from Fiji, and the purple color form known as "Milka" with white growing tips.

They live in symbiosis with zooxanthellae and can feed on light. In general Stylophora are still quite undemanding and hardy for SPS, they can be maintained even with higher nutrient levels. However, for optimal color development they need strong light and low nutrient levels, as well as the right trace elements. The current should be very strong as typical for SPS.

Zoanthus is a genus of colonial encrusting anemones. They are extremely popular in marine aquaristics, because their species form particularly many bright color morphs - especially with blue light + filter a delight - and the maintenance is uncomplicated. So many fans can be found collecting different Zoanthus color morphs. Zoanthus make few demands on water quality and often thrive better in elevated nutrient levels than in completely clean water.

They are moderately light hungry and require stronger lighting - around 100 PAR - than other soft corals. You can tell that light levels are too low when they are stretching their bodies toward the light, and too strong when they are struggling and shrinking. Strong current is also important. There is often confusion over the exact classification of encrusting anemones to Zoanthus and the related genus Palythoa - but in principle it is quite easy to tell them apart: Palythoa have a rough surface as they absorb sand into their tissues, and their tentacles are more pointed than those of Zoanthus. Therefore, many of the encrusting anemones that are often referred to as "paly" are not palythoa at all, but zoanthus. They grow as a mat covering the rock, and their polyps are associated with a basal tissue known as coenenchyme.

Zoanthus encrusting anemones can be toxic because, like other encrusting anemones, they also store the palytoxin produced by dinoflagellates - though concentrations in their tissues are often lower than in Palythoa species. Nevertheless, contact of mucous membranes (mouth, nose, eyes and "where no light shines") and open wounds to the tissue secretion and mucus should be avoided as much as possible: that is, especially when fragmenting, it is best to wear gloves and protective goggles. It is best not to injure the animals mechanically, and be careful because the polyps can also spit. Palytoxin is a cytotoxin and can cause a variety of symptoms from a metallic taste on the tongue to flu symptoms and muscle paralysis, depending on which cells it affects. Since Zoanthus can multiply heavily - and mechanical removal is therefore rather unfavorable - it is recommended not to put them on the main reef setup, but to place them separately.